• Microbiology and Biotechnology Letters
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• v.31 no.2
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• pp.171-176
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• 2003

Productivity of biosurfactant (rhamnolipid) by Pseudomonas aeuginosa F722 was investigated in the several culture conditions and culture composition. Biosurfactant production by P. aeuginosa F722 was amounted to 0.78 g/l as the result of the nitrogen sources and carbon sources without investing of optimum conditions. As for that one was investigated, biosurfactant production by P. aeruginosa F722 was amounted to 1.66 g/l. Biosurfactant production increased twofold because the composition of a modified C-medium was investigated efficiently. $NE_4$Cl or $NaNO_2$ inorganic nitrogens and yeast extract or trypton organic nitrogens were effective, but others inorganic nitrogens and organic nitrogens tested were not efficient far biosurfactant production by P. aeruginosa F722. The optimum concentration of $NH_4$Cl; inorganic nitrogen and yeast extract; organic nitrogen were 0.05% and 0.1%, respectively. In various carbon sources, others with the exception of hydrophobic property substrate (n-alkane) and hydrophilic property substrate (glucose, glycol) were not found to be effective fur biosurfactant production, and 3.0% was better in yield than other concentration of glucose. This yielded C-to-N ratios between 17 and 20. In our experiment, the highest biosurfactant production by P. aeruginosa F722 were observed in 5 days cultivation, containing glucose 3.0%, $NH_4$Cl 0.05%, and yeast extract 0.1% and C-to-N ratio was 20. Optimal pH and temperature for biosurfactant production were 7.0 and $35^{\circ}C$, respectively. Under the optimal culture conditions with glucose, biosurfactant production was amounted to 1.66 g/l. Velocity of biosurfactant production and strain growth increased after nitrogen depletion. The average surface tension of 30 mN/m after the 3 days of incubation under optimal culture condition was measured by ring tensionmeter.

• Microbiology and Biotechnology Letters
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• v.45 no.2
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• pp.162-167
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• 2017

For the production of bioethanol by the synchronous saccharification and fermentation (SSF) process, bio-capsule formation was attempted. Many saccharifying fungal strains and fermentative yeast strains were first screened. Aspergillus sp. BCNU 6200, Penicillium sp. BCNU 6201, and P. chrysogenum KACC 44363 were found to be excellent producers of saccharifying enzymes such as ${\alpha}$-amylase and glucoamylase. Saccharomyces cerevisiae IFO-M-07 showed the highest ethanol productivity among the tested strains. Secondly, we determined the optimal conditions for pellet formation, and those for bio-capsule formation. All the tested fungal strains formed pellets, and the optimal conditions for bio-capsule formation were $28^{\circ}C$ and 120 rpm. Lastly, SSF process was performed using a bio-capsule. An ethanol yield of 3.9% was achieved by using the Aspergillus sp. BCNU 6200 bio-capsule (Aspergillus sp. BCNU 6200 + S. cerevisiae IFO-M-07) at $30^{\circ}C$ with shaking at 120 rpm during the 10 days of incubation. The results provide useful information on the application of a bio-capsule in bioethanol production under the SSF process.

• Korean Journal of Construction Engineering and Management
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• v.19 no.6
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• pp.115-123
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• 2018

The primary objective of this study is to develop an all-in-one based steel pipe pile cutting robot prototype that improves the conventional steel pipe pile head cutting work in safety, quality, and productivity. For this, the following research works are conducted sequentially; 1)literature review and expert survey, 2)selection of core technology using AHP analysis, 3)deduction of detail design, 4)verification of structural stability, 5)development of full-scale prototype. As a result leveling laser and laser detector(94.46), plasma cutter(96.72), rotary grapple(98.45) are selected as a core technologies. As an outcome, it is analyzed that gripper, cylinder pivot bracket and gripper base are structurally stable. Their maximum stresses are shown as 43.0%, 19.4%, 5.3% compared to their yield strength respectively. The development of full-scale prototype in this study will be utilized for the development of the all-in-one attachment based steel pipe pile cutting robot commercialization model.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.3
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• pp.320-326
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• 2017

Multistage deep-drawing technology is used widely in the production of mobile phone battery cases to improve productivity and economy. To ensure adequate capacity and rigidity, such cases are fabricated as a rectangular cup with a high slender ratio. The multistage deep-drawing of a rectangular cup entails a high slender ratio, and the heights of the product sides may be non-uniform because of the complicated deformation mechanisms. This causes problems in product assembly that affects the surface quality of the case. This study examined a blank shape that minimizes the height variations of the product to resolve the aforementioned problems. Optimization design and analysis were performed to identify the shape that yields the least variation. The long and short sides of an oval blank were set as the design variables. The objective function was set to yield the lowest height difference, and the thickness reduction rate of the product was set to the target range. In addition, the height of the final shape was set as a constraint. The height difference was minimized successfully using the optimized design. The design process of the initial blank for all rectangular shapes can be automated in the future.

• Korean Journal of Plant Resources
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• v.31 no.1
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• pp.90-94
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• 2018

The 'Hongsil' strawberry ($Fragaria{\times}ananassa$ Duch.) is a new cultivar released by Gyeongsangnam-do Agricultural Research & Extension Services in 2015. This cultivar originated from a 2011 cross between '802a312' and 'Okmae' and exhibited suitable fruit characteristics for export due to the high soluble solids content and firmness of the fruit. The breeding line '1116-74-15' was selected as an elite line after examining its characteristics and productivity from 2013 to 2014. A field trial of this line was conducted on a farm in 2015, and it was registered as 'Hongsil' thereafter. The 'Hongsil' strawberry demonstrates intermediate plant type and moderate vigor in growth. It is suitable for forcing culture due to its early flower bud differentiation and low chilling requirement. The soluble solids content of 'Hongsil' is $10.0^{\circ}Brix$, which is approximately $0.4^{\circ}Brix$ higher than that of 'Seolhyang' The Fruit firmness of 'Hongsil' is $13.1g{\cdot}mm^{-2}$, similar to that of 'Maehyang'. Fruits of 'Hongsil' are long conical having a red skin color and marketable yield is $4,269kg{\cdot}10a^{-1}$ which is 16% higher than that of 'Maehyang'. The 'Hongsil' cultivar is sensitive to powdery mildew, and it therefore warrants further investigation regarding disease control.

• KSBB Journal
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• v.21 no.6 s.101
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• pp.479-483
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• 2006

[ ${\beta}-Glucan$ ], one of the cell wall components, is most plentiful polysaccharides in cell wall and has several advantages in immune system. In yeast ${\beta}-glucan$ is mainly contained in the yeast cell wall, and thus it is important to produce high levels of cell mass for the mass production of yeast ${\beta}-glucan$. The best carbon and nitrogen sources on cell mass production were high fructose syrup and yeast extract. Response surface methodology (RSM) was very potential tool for the optimization of process factor and medium component. It was applied to estimate the effects of medium components on the production of cell mass. Optimal concentrations of high fructose syrup and yeast extract by response surface methodology were 8.0% (v/v) and 5.2% (w/v), respectively and the cell mass predicted was $17.0\;g/{\ell}$ at 20 h of cultivation.

• Korean Journal of Construction Engineering and Management
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• v.19 no.2
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• pp.117-125
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• 2018

The primary objectives of this study are to develop a detail design of automated PHC pile head cutting machine and structural stability analysis of detail design that improves the conventional head cutting work in safety, quality, and productivity. For this, the following research works are conducted sequentially; 1)literature review and field study, 2)expert survey and interview, 3)selection of core technology using AHP analysis, 4)deduction of detail design 5) verification of structural stability. As an outcome, it is analyzed that gripper and gripper bearing shaft are structurally stable. Their maximum stresses are shown as 15.93%, 10.58% compared to their yield strength respectively. The results of detail design and structural stability analysis in this study will be utilized for the actual development of the automated PHC pile cutting machine prototype.

• Korean Chemical Engineering Research
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• v.49 no.2
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• pp.129-136
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• 2011

Simulated Moving Bed(SMB) process consists of multiple chromatographic columns, which are usually partitioned into four zones. Such a process characteristic allows a continuous binary separations those are impracticable in conventional batch chromatographic processes. Compared with batch chromatography, SMB has advantages of continuity, high purity and productivity. Various researches have been reported for the integration of reaction and recovery during process operation on the purpose of economics and effectiveness. Simulated Moving Bed Reactor(SMBR) is introduced to combine SMB as a continuous separation process and reactor. Several cases of SMBR have been reported for diverse reactions with catalytic, enzymatic and chemical reaction on ion exchange resin as main streams. With an early type of fixed bed using catalyst, SMBR has been developed as SMB using fluidized enzyme, SMB with immobilized enzyme and SMB with discrete reaction region. For simple modeling and optimization of SMBR, a method considering convection only is possible. A complex method considering axial dispersion and mass transfer resistance is needed to explain the real behavior of solutes in SMBR. By combining reaction and separation, SMBR has benefits of lower installation cost by minimizing equipment use, higher purity and yield by avoiding the equilibrium restriction in case of reversible reaction.

• Journal of Environmental Science International
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• v.27 no.5
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• pp.291-297
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• 2018

Vertical farming systems offer many advantages in urban spaces. They have also been proposed as an engineering solution to increase the productivity per unit area of cultivated land by extending crop production in the vertical dimension. However, soil water retention is a major constraint affecting the plant environment. This study analyzed the effects of growth environment of Tropaeolum majus and Fragaria spp., on the vertical farming system, by using four different types of cover material types including sphagnum moss (Control), a shading net (S.N.), multi-layered fabric (M.L.F.), and non-woven fabric (N.W.F.). The volumetric soil moisture contents and plant characteristics were investigated from May to September 2014. Plant materials were individually cultivated in hanging baskets measuring $30{\times}17{\times}17cm$, filled with a mixture of soil and perlite, and placed at 1.5m height. Each treatment was performed in quadruplicate and consisted of five plants, amounting to a total of 20 plants. The analysis indicated that different covers were associated with multiple functions and soil water retention improvements may have a positive impact on the vertical farming system. The difference in soil water retention increased in the following order: M.L.F. > Control > N.W.F. > S.N.. Furthermore, the differences in plant height and survival rate increased in the following order: M.L.F. > Control > N.W.F. > S.N. Therefore, M.L.F yielded satisfactory good response for the vertical farming system of cover materials. Our results clearly demonstrate that vertical spaces represent an attractive alternative to urban farming and suggest that further increases in yield may be achieved via different cover materials in vertical farming using hanging baskets.

• Journal of Mushroom
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• v.4 no.1
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• pp.33-38
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• 2006

Bottle cultivation was conducted to clarify varietal differences and physiological characteristics of oyster mushroom under different temperatures. Mushroom pinheading and yield in each temperature showed different results according to the strains. Specially, Weonhyeong3-ho could not sprout over $16.5^{\circ}C$, but after pinheading at $13^{\circ}C$, its fruitbody was able to grow normally at all tested temperatures. Sambok, a high temperature strain, sprouted at $10^{\circ}C$ and then withered up. Fruitbody of this strain obtained at $13^{\circ}C$ could not grow normally at $10^{\circ}C$ and $25^{\circ}C$ conditions. Colour of fruitbodies turned close to white at high temperature. On the other hand, at low temperature, strains with gray fruitbody changed close to black and those with brown fruitbody turned to dark brown. With regards to fruiting trait, pinheading aspects were good even at low temperature. Those were, however, uneven and sprouted in patches and resulted in low quality and productivity as the temperature increased. When black fruitbody at $13^{\circ}C$ were moved to $23^{\circ}C$ and then to $13^{\circ}C$ again, colour of fruitbody turned to white and then recovered to blackish gray. These results confirmed that the colour of fruitbody responds to cultivation temperature.